The invention is based on a fuel injection nozzle for internal combustion engines. In a known injection nozzle of this type (German Auslegeschrift No. 10 49 635), two induction coils are disposed coaxially with one another, each being provided with a central opening passing through it and into which an armature dips under the influence of the valve needle. The two armatures are embodied by two magnetically conductive longitudinal sections of one through bore, the sections being separated from one another by an intermediate section of magnetically nonconductive material. The two induction soils are disposed in the measurement branch of a bridge of an appliance functioning with carrier frequency modulation. This arrangement requires two induction coils and is also relatively expensive in terms of the other elements of the measuring circuit. It is furthermore either not possible or possible only with additional circuit elements to generate an abrupt change in inductivity of the coil at the onset of the opening stroke and at the end of the closing stroke of the valve needle, and in this manner to detect precisely the onset and the end of an injection procedure.